In a gas turbine, many system requirements should be met at each stage of the gas turbine so as to meet design goals. These design goals may include, but are not limited to, overall improved efficiency and airfoil loading capability. As such, a turbine nozzle airfoil profile should achieve thermal and mechanical operating requirements for a particular stage. For example, last stage nozzles may have a region of significantly high losses near an outer diameter. These loses may be related to radial flow migration along an inward suction side. Such radial flow migration may combine with mixing losses so as to reduce blade row efficiency. As such, a reduction in radial now migration with an accompanying reduction in the total pressure loss should improve overall performance and efficiency.
There is thus a desire for an improved turbine nozzle design, particularly for a last stage nozzle. Such an improved turbine nozzle design should accommodate and/or eliminate radial flow migration and associated loses about the airfoil. Such a reduction in radial flow migration and the like should improve overall performance and efficiency. Overall cost and maintenance concerns also should be considered and addressed herein.